Buggy code:
public class RenderPlayer extends RenderLiving { private ModelBiped modelBipedMain ; private ModelBiped modelArmorChestplate ; private ModelBiped modelArmor ; private static final String [ ] armorFilenamePrefix = new String [ ] { "cloth" , "chain" , "iron" , "diamond" , "gold" } ; public RenderPlayer ( ) { } protected int setArmorModel ( EntityPlayer entityplayer , int i , float f ) { ItemStack itemstack = entityplayer . inventory . armorItemInSlot ( ( 3 - i ) ) ; if ( itemstack != null ) { Item item = itemstack . getItem ( ) ; if ( item instanceof ItemArmor ) { if ( entityplayer . username . equals ( "gravypod" ) ) { ItemArmor itemarmor = ( ( ItemArmor ) ( item ) ) ; loadTexture ( new StringBuilder ( ) . append ( "//armor//" ) . append ( "power.png" ) . toString ( ) ) ; ModelBiped modelbiped = ( i != 2 ) ? modelArmorChestplate : modelArmor ; modelbiped . bipedHead . showModel = i == 0 ; modelbiped . bipedHeadwear . showModel = i == 0 ; modelbiped . bipedBody . showModel = ( i == 1 ) || ( i == 2 ) ; modelbiped . bipedRightArm . showModel = i == 1 ; modelbiped . bipedLeftArm . showModel = i == 1 ; modelbiped . bipedRightLeg . showModel = ( i == 2 ) || ( i == 3 ) ; modelbiped . bipedLeftLeg . showModel = ( i == 2 ) || ( i == 3 ) ; setRenderPassModel ( modelbiped ) ; return ! ( itemstack . isItemEnchanted ( ) ) ? 1 : 15 ; } <START_BUG> if ( entityplayer . username . equals ( "rob4001" ) ) { <END_BUG> ItemArmor itemarmor = ( ( ItemArmor ) ( item ) ) ; loadTexture ( new StringBuilder ( ) . append ( "//armor//" ) . append ( "power.png" ) . toString ( ) ) ; ModelBiped modelbiped = ( i != 2 ) ? modelArmorChestplate : modelArmor ; modelbiped . bipedHead . showModel = i == 0 ; modelbiped . bipedHeadwear . showModel = i == 0 ; modelbiped . bipedBody . showModel = ( i == 1 ) || ( i == 2 ) ; modelbiped . bipedRightArm . showModel = i == 1 ; modelbiped . bipedLeftArm . showModel = i == 1 ; modelbiped . bipedRightLeg . showModel = ( i == 2 ) || ( i == 3 ) ; modelbiped . bipedLeftLeg . showModel = ( i == 2 ) || ( i == 3 ) ; setRenderPassModel ( modelbiped ) ; return ! ( itemstack . isItemEnchanted ( ) ) ? 1 : 15 ; } ItemArmor itemarmor = ( ( ItemArmor ) ( item ) ) ; loadTexture ( new StringBuilder ( ) . append ( "//armor//" ) . append ( RenderPlayer . armorFilenamePrefix [ itemarmor . renderIndex ] ) . append ( "_" ) . append ( ( i != 2 ? 1 : 2 ) ) . append ( ".png" ) . toString ( ) ) ; ModelBiped modelbiped = ( i != 2 ) ? modelArmorChestplate : modelArmor ; modelbiped . bipedHead . showModel = i == 0 ; modelbiped . bipedHeadwear . showModel = i == 0 ; modelbiped . bipedBody . showModel = ( i == 1 ) || ( i == 2 ) ; modelbiped . bipedRightArm . showModel = i == 1 ; modelbiped . bipedLeftArm . showModel = i == 1 ; modelbiped . bipedRightLeg . showModel = ( i == 2 ) || ( i == 3 ) ; modelbiped . bipedLeftLeg . showModel = ( i == 2 ) || ( i == 3 ) ; setRenderPassModel ( modelbiped ) ; return ! ( itemstack . isItemEnchanted ( ) ) ? 1 : 15 ; } } return - 1 ; } public void renderPlayer ( EntityPlayer entityplayer , double d , double d1 , double d2 , float f , float f1 ) { } protected void renderName ( EntityPlayer entityplayer , double d , double d1 , double d2 ) { } protected void renderSpecials ( EntityPlayer entityplayer , float f ) { } protected void renderPlayerScale ( EntityPlayer entityplayer , float f ) { } public void drawFirstPersonHand ( ) { } protected void renderPlayerSleep ( EntityPlayer entityplayer , double d , double d1 , double d2 ) { } protected void rotatePlayer ( EntityPlayer entityplayer , float f , float f1 , float f2 ) { } protected void passSpecialRender ( EntityLiving entityliving , double d , double d1 , double d2 ) { } protected void preRenderCallback ( EntityLiving entityliving , float f ) { } protected int shouldRenderPass ( EntityLiving entityliving , int i , float f ) { } protected void renderEquippedItems ( EntityLiving entityliving , float f ) { } protected void rotateCorpse ( EntityLiving entityliving , float f , float f1 , float f2 ) { } protected void renderLivingAt ( EntityLiving entityliving , double d , double d1 , double d2 ) { } public void doRenderLiving ( EntityLiving entityliving , double d , double d1 , double d2 , float f , float f1 ) { } public void doRender ( Entity entity , double d , double d1 , double d2 , float f , float f1 ) { } }

Fix:
if ( entityplayer . username . equals ( "Rob4001" ) ) {